主题：求助：自动编号。

 或者这样改

Select e.DataCol.Name
    Case "制单日期","入库类型"
        If e.DataRow.IsNull("制单日期") OrElse e.DataRow.IsNull("入库类型") Then
            e.DataRow("入库单号") = Nothing
        Else
            Dim d As Date = e.DataRow("制单日期")
            Dim y As Integer = d.Year
            Dim m As Integer = d.Month
            'Dim Days As Integer = Date.DaysInMonth(y,m)
            Dim fd As Date = New Date(y,m,1) '获得该月的第一天
            Dim ld As Date = fd.AddMonths(1)

            Dim bh As String = e.DataRow("入库类型") & "-" & Format(d,"yyyyMM") & "-" '生成编号的前缀
            If e.DataRow("入库单号").StartsWith(bh) = False '如果单据编号前缀不符
                Dim max As String
                Dim idx As Integer
                Dim flt As String
                flt = "入库类型 = '" & e.DataRow("入库类型") & "' And 制单日期 >= #" & fd & "# And 制单日期 < #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")
                max = e.DataTable.Compute("Max(入库单号)",flt) '取得该月的相同工程代码的最大单据编号
                If max > "" Then '如果存在最大单据编号
                    idx = CInt(max.Substring(12,4)) + 1 '获得最大单据编号的后四位顺序号,并加1
                Else
                    idx = 1 '否则顺序号等于1
                End If
                e.DataRow("入库单号") = bh & Format(idx,"0000")
            End If
        End If
End Select

If e.DataCol.Name = "入库类型" Then
    e.DataRow("订单状态") = "已收货,待清点"
End If

If e.DataCol.Name = "制单日期" Then
    Dim dr As DataRow = e.DataRow
    Dim dt As Date = dr("制单日期")
    dr("预计完成时间") = dt.AddHours(24)
End If